Oh, what a delightful little puzzle you have there! Let's see... how about the word "treasure"? It has eight letters, and the third letter is indeed an 'r.' Keep exploring the beauty of words, my friend!
caripace
garbage
The only 8 letter word you can get out of CESERCNT is crescent
Some six letter words with the second letter R and the third letter I are:arisesbribedbridalbridgebridlebrightcringecrisiscrispycriticdrippydriveldriverfridgefriendfrightfrigidfrillyfringefriskyfrizzygrievegrillegrinchgrittyorientoriginoriolepriestprimalprimerprinceprisonprivettribaltrickytrifletripletripodtrivettriviaurinalwriterwrithe
Perfected is a synonym for finished. The third letter is an r.
perfect?
territory
through
preserve
cobbler
blurryblurtschurchchurnsflurryfourthhourlymournspouredscurryslurpssouredspurnssturdytoured
certain